The following definitions are used by the American Association of Textile Chemists and Colorists (AATCC) in the AATCC Technical Manual, Vol. 77, pp. 409 and 413, 2002, American Association of Textile Chemists and Colorists, Research Triangle Park, N.C.
xe2x80x9cDetergentxe2x80x9d is a cleaning agent containing one or more surfactants as the active ingredient(s). xe2x80x9cSoilxe2x80x9d is dirt, oil, or other substances not normally intended to be present on a substrate, such as a textile material. xe2x80x9cSoilingxe2x80x9d in textiles is a process by which a textile substrate becomes more or less uniformly covered with, or impregnated with, soil. xe2x80x9cSoil resist agentxe2x80x9d is a material applied to, or incorporated in, carpet face fiber that retards and/or limits the build-up of soil. xe2x80x9cSurfactantxe2x80x9d is a soluble or dispersible material that reduces the surface tension of a liquid, usually water.
The same source defines xe2x80x9cTextile floor coveringxe2x80x9d as xe2x80x9can article having a use-surface composed of textile material and generally used for covering floors.xe2x80x9d Hereinafter the term xe2x80x9ccarpetxe2x80x9d is used to describe such textile floor covering.
The Kirk-Othmer Concise Encyclopedia of Chemical Technology, 3rd Edition, John Wiley and Sons, New York N.Y., 1985 in a discussion of xe2x80x9cSurfactants and Detersive Systemsxe2x80x9d at p. 1142 states xe2x80x9cThe term detergent is often used interchangeably with surfactant.xe2x80x9d
In the prior art, residual oils or detergents left on the fiber of a carpet after manufacture, after the application of soil resist agents, or after carpet cleaning by shampooing, have been extensively reported as causes of subsequent soiling. For instance, W. F. Taylor and H. J. Demas xe2x80x9cThe Why""s of Carpet Soilxe2x80x9d, Textile Ind., November 1968, pp. 83-87 comment at p. 83-84: xe2x80x9cSevere soiling may occur if the fiber contains an oily film. This phenomena is responsible for most resoiling problems after a carpet has been shampooed where the detergent is not completely removed. Improper lubricants on the fiber can cause this effect, as will airborne greases which settle onto the carpet surface.xe2x80x9d The authors equate oils and detergents as causes. The authors continue to list factors xe2x80x9cthought to affect soiling of nylon carpetsxe2x80x9d and state (p. 87) xe2x80x9cThe effect of residual oily materials causing increased soiling of textile materials is well documented in the literature. Severe soiling may occur if the fiber contains an oily film.xe2x80x9d Elsewhere, W. Postman, in xe2x80x9cSpin Finishes Explainedxe2x80x9d, Textile Research Journal, Vol. 50 #7, 444-453 (July 1980), notes at p. 445, that xe2x80x9c . . . since poor scourability can cause dyeing problems and potential soiling spots, lubricants must come off the yarn under mild scouring conditions . . . .xe2x80x9d
Technical information for the carpet manufacturing trade is replete with warnings about the worsened soiling associated with, and attributed to, excessive amounts of oils or detergents. Current World Wide Web sites include:
1. http://www.carpetbuyershandbook.com/common_cleaning_challenges.htm
Carpet Buyers Handbook web site (accessed Jul. 25, 2002):
xe2x80x9cOften resoiling can be attributed to detergent residues left behind during cleaning. Detergents, by design, attract soil. By leaving detergent in carpet after cleaning, detergents rapidly attract soil.xe2x80x9d
2. http://www.hoovercompany.com/ftp/cguide.pdf
Hoover Consumer Guide to Carpet Cleaning web site (accessed Jul. 25, 2002):
xe2x80x9cSome shampoos contain oil which can contribute to resoiling; . . . xe2x80x9d
3. http://www.carpet-rug.com/drill_downxe2x80x942.cfm?page=14andsub=3
xe2x80x9cRinse all detergent from the carpet to prevent accelerated resoiling.xe2x80x9d
4. http://cms.3m.com/cms/US/en/2-78/iFeRkFQ/view.jhtml
3M web site (accessed Jul. 25, 2002):
xe2x80x9cShampooing may not only leave behind a soapy residue that often masks the carpet""s protective finish, but it can attract and hold dirt.xe2x80x9d
5. hftp://antron.dupont.com/content/how_to/ant02xe2x80x9406.shtml
DuPont Antron* web site, from Section C, Deep Cleaning (accessed Jul. 25, 2002):
xe2x80x9cYou also need to be aware that some methods use detergents that cause resoil. This happens when detergents remain on the fiber surface after cleaning. These detergents will continue to attract soil causing the carpet to look dirty.xe2x80x9d
The manufacturers of dispersed soil resist formulations have consequently striven to use only enough dispersing agent in their formulations to provide a stable dispersion in the formulation as shipped. The results of this restriction are shown in Table 1 as the ratio of fluorochemical to dispersant in typical commercial carpet soil resist formulations. The calculated weight ratio of fluorochemical:dispersing agent ranges from 14:1 to 30:1 in Table 1.
Typically, soil resist formulations are shipped in a concentrated form, and diluted with water at the site of application. Commercially, dispersing agent levels in such formulations are kept close to the minimum needed to assure dispersion stability during shipment, dilution, and use.
It is desirable to have improved soil resist agents for treatment of fibrous substrates such as carpets during manufacture, and for use in or after cleaning agents used on soiled carpets. Such an improved soil resist agent would provide better resistance to soiling.
The present invention comprises carpet treated with a specific soil resist agent formulated in dispersions containing substantially more surfactants than are necessary to assure a stable dispersion. Despite teachings that residual oils or surfactants lead to quicker soiling of carpet, it has been found that increasing the level of surfactant present in the soil resist agent improves its performance.
The present invention comprises a carpet treated with a soil resist agent comprising a dispersion in water or water and solvent of a) a polyfluoro organic compound having at least one of a urea, urethane, or ester linkage, and b) at least one anionic non-fluorinated surfactant, wherein the ratio of polyfluoro organic compound to surfactant is from about 0.075:1.0 to about 5:1.